1. Field of the Invention
The present invention relates to mechanical winding machines which are designed to wind large diameter rolls of a continuously-feeding web or film and, more particularly, to a simple mechanical high-speed winder capable of the semi-automatic transfer of the web or film from a full to an empty spindle.
The overall operating efficiency of industries producing high volume malleable sheet-like material such as plastic, paper, etc. requires a method by which a continuously conveyed web or film can be (1) safely removed from the output station of the web-producing machine or process, (2) packed in a readily useable manner, and (3) stored efficiently. Quite evidently, in order to accommodate any high speed production, the method of film retrieval should be as rapid as possible, but it must also be sufficiently precise so as to minimize or avoid damage to the product. Furthermore, in order to maintain an efficient operation, the entire retrieval process should be characterized by the use of simple mechanisms which are capable of being quickly and easily repaired in case of a mechanical malfunction or breakdown. Consequently, the art of mechanical winding of continuously-fed or conveyed webs or films has become very important to industries involved in such production.
Efforts to satisfy the above requirements account for the continuing development of the art of winding sheet product rolls in the plastic, textile, and paper industries. Large diameter rolls, in particular, provide a convenient means for safely accumulating, at either high or low speed, the continuously produced web or film. Furthermore, rolls of sheet product are easy to handle with conventional warehousing and shipping equipment.
2. Discussion of the Prior Art
Conventional mechanical winding devices basically include at least one winding base which accommodates a winding spindle onto which there is guided a sheet product, and a power source which drives the spindle in a preferred rotational direction so that the sheet is accumulated or wound on the spindle. The speed of rotation is essentially dependent upon the speed at which the sheet is produced. In the textile industry the necessarily utilized rotational speed is not as high as in the plastic and paper industries.
Known methods of winding also provide for apparatus which include a stationary guiding device for receiving the sheet product from the output station and directing it to the spindle which is mounted on the winding base at the only winding position. Upon accumulation or winding of the desired amount of sheet on the spindle, an empty spindle must be introduced to the exact same winding position as the full spindle so as to be able to receive the sheet product as it exits from the stationary guiding device. The replacement procedure used to change from the full to the empty spindle is quite critical to the retrieval efficiency of the sheet product, since, in any continuous output process any downtime reduces efficiency and increases production costs.
One method of retrieving sheet product, generally associated with the textile industry, incorporates a simple winding spindle secured in a stand at a winding station and rotated about its own axis by a portable hydraulic or electric motor. After the roll is wound to the desired amount, the web is manually transferred to an empty spindle while the full roll together with support stand is removed from the winding station and replaced with the empty spindle and its accompanying support stand. This method, however, is not amenable to high speed product retrieval because the manual web-exchange technique would not be capable of accommodating high speed sheet output such as is necessitated in the plastics and paper industry. It is also inconvenient because a machine tenderer must be constantly available to perform the required manual changeover procedure.
Another well known method of winding large diameter rolls involves the use of a turret-type winder which is generally characterized by a stationary base having a rotatable turret head which, in turn, has two or more spindle-accommodating positions. In use, a machine operator mounts an empty spindle at a spindle-accommodating position and, thereafter, the turret head is rotated to place the spindle at a specific winding station adjacent to the sheet guiding device. Then the spindle is then rotated by an electric motor about its own axis, and the web or plastic film is wound thereon. Once a roll of desired size has been wound, the turret is rotated or indexed about its axis so that an empty spindle is brought into winding position, the web is automatically cut off and is concurrently automatically transferred from the full spindle onto the empty spindle. The full roll is then removed manually from the winder by the operator. As the full spindle is rotated away from the winding station the path of the continuously-fed sheet product is of necessity distorted to follow the moving take-up spindle. Therefore, a sophisticated and multicomponent system of drives must be employed in order to avoid sideways slippage of the sheet. Furthermore, the entire turret-type apparatus is constituted of expensive and complicated equipment demanding a comparatively expensive support package consisting of a large supply of different types of parts and requiring highly trained technicians to maintain continuous operation.